dmaengine: of-dma: Fix of_dma_router_xlate's of_dma_xlate handling

[ Upstream commit 5b2aa9f918f6837ae943557f8cec02c34fcf80e7 ]

of_dma_xlate callback can return ERR_PTR as well NULL in case of failure.

If error code is returned (not NULL) then the route should be released and
the router should not be registered for the channel.

Fixes: 56f13c0d9524c ("dmaengine: of_dma: Support for DMA routers")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200806104928.25975-1-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 1e1f2986eba8f194767362bd96d8a866dba1097a..86c591481dfe96f18a90e9b9a8ebd2d8c80d5edd 100644 (file)
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -72,12 +72,12 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec,
                return NULL;
 
        chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target);
-       if (chan) {
-               chan->router = ofdma->dma_router;
-               chan->route_data = route_data;
-       } else {
+       if (IS_ERR_OR_NULL(chan)) {
                ofdma->dma_router->route_free(ofdma->dma_router->dev,
                                              route_data);
+       } else {
+               chan->router = ofdma->dma_router;
+               chan->route_data = route_data;
        }
 
        /*